Python SVG parser
Question:
I want to parse an SVG file using python to extract coordinates/paths (I believe this is listed under the “path” ID, specifically the d=”…”/>). This data will eventually be used to drive a 2 axis CNC.
I’ve searched on SO and Google for libraries that can return the string of such paths so I can further parse it, but to no avail. Does such a library exist?
Answers:
Ignoring transforms, you can extract the path strings from an SVG like so:
from xml.dom import minidom
doc = minidom.parse(svg_file) # parseString also exists
path_strings = [path.getAttribute('d') for path
in doc.getElementsByTagName('path')]
doc.unlink()
Getting the d-string can be done in a line or two using svgpathtools.
from svgpathtools import svg2paths
paths, attributes = svg2paths('some_svg_file.svg')
paths is a list of svgpathtools Path objects (containing just the curve info, no colors, styles, etc.).
attributes is a list of corresponding dictionary objects storing the attributes of each path.
To, say, print out the d-strings then…
for k, v in enumerate(attributes):
print(v['d']) # print d-string of k-th path in SVG
The question was about extracting the path strings, but in the end the line drawing commands were wanted. Based on the answer with minidom, I added the path parsing with svg.path to generate the line drawing coordinates:
#!/usr/bin/python3
# requires svg.path, install it like this: pip3 install svg.path
# converts a list of path elements of a SVG file to simple line drawing commands
from svg.path import parse_path
from svg.path.path import Line
from xml.dom import minidom
# read the SVG file
doc = minidom.parse('test.svg')
path_strings = [path.getAttribute('d') for path
in doc.getElementsByTagName('path')]
doc.unlink()
# print the line draw commands
for path_string in path_strings:
path = parse_path(path_string)
for e in path:
if isinstance(e, Line):
x0 = e.start.real
y0 = e.start.imag
x1 = e.end.real
y1 = e.end.imag
print("(%.2f, %.2f) - (%.2f, %.2f)" % (x0, y0, x1, y1))
I want to parse an SVG file using python to extract coordinates/paths (I believe this is listed under the “path” ID, specifically the d=”…”/>). This data will eventually be used to drive a 2 axis CNC.
I’ve searched on SO and Google for libraries that can return the string of such paths so I can further parse it, but to no avail. Does such a library exist?
Ignoring transforms, you can extract the path strings from an SVG like so:
from xml.dom import minidom
doc = minidom.parse(svg_file) # parseString also exists
path_strings = [path.getAttribute('d') for path
in doc.getElementsByTagName('path')]
doc.unlink()
Getting the d-string can be done in a line or two using svgpathtools.
from svgpathtools import svg2paths
paths, attributes = svg2paths('some_svg_file.svg')
paths is a list of svgpathtools Path objects (containing just the curve info, no colors, styles, etc.).
attributes is a list of corresponding dictionary objects storing the attributes of each path.
To, say, print out the d-strings then…
for k, v in enumerate(attributes):
print(v['d']) # print d-string of k-th path in SVG
The question was about extracting the path strings, but in the end the line drawing commands were wanted. Based on the answer with minidom, I added the path parsing with svg.path to generate the line drawing coordinates:
#!/usr/bin/python3
# requires svg.path, install it like this: pip3 install svg.path
# converts a list of path elements of a SVG file to simple line drawing commands
from svg.path import parse_path
from svg.path.path import Line
from xml.dom import minidom
# read the SVG file
doc = minidom.parse('test.svg')
path_strings = [path.getAttribute('d') for path
in doc.getElementsByTagName('path')]
doc.unlink()
# print the line draw commands
for path_string in path_strings:
path = parse_path(path_string)
for e in path:
if isinstance(e, Line):
x0 = e.start.real
y0 = e.start.imag
x1 = e.end.real
y1 = e.end.imag
print("(%.2f, %.2f) - (%.2f, %.2f)" % (x0, y0, x1, y1))